1. Field of the Invention
This invention pertains to the field of grafted aromatic polyamide or copolyamide fibers.
2. Description of Related Art
U.S. Pat. Nos. 6,045,907 and 6,358,451 to Rebouillat disclose poly(p-phenylene terephthalamide) fibers that have been grafted with nitrobenzyl, allyl, or nitrostilbene groups to increase adhesion of the fibers to rubber. A process for making the grafted fibers that requires wet or never-dried as-spun para-aramid fibers to prepare the base-activated fibers for the grafting step is also disclosed. References are cited therein that disclose alternative processes for preparing grafted fibers to improve their adhesion with a variety of polymeric matrices.
There is an ongoing need to provide para-aramid type fibers that have enhanced adhesion for reinforcement of polymeric matrices.